Serum HBcrAg is better than HBV RNA and HBsAg in reflecting intrahepatic covalently closed circular DNA.

The correlation between serum HBcrAg and HBV RNA is unclear, and correlations of intrahepatic cccDNA with HBcrAg, HBV RNA and HBsAg are rarely reported in the same cohort. This study aimed to assess the correlation of HBcrAg with HBV RNA and HBsAg, and investigate whether serum HBcrAg is superior to serum HBV RNA and HBsAg in reflecting intrahepatic HBV cccDNA in HBeAg-positive and HBeAg-negative CHB patients. In this study, 85 HBeAg-positive and 25 HBeAg-negative patients who have never received antiviral therapy were included. Among HBeAg-positive patients, HBcrAg was correlated positively with HBsAg (r = 0.564, P < 0.001) and HBV RNA (r = 0.445, P < 0.001), and HBV RNA was also correlated positively with HBsAg (r = 0.323, P = 0.003). Among HBeAg-negative patients, no significant correlation was observed between HBcrAg, HBsAg and HBV RNA. By multivariable linear regression, HBcrAg (β = -0.563, P < 0.001), HBsAg (β = -0.328, P < 0.001) and HBV RNA (β = 0.180, P = 0.003) were all associated with cccDNA levels among HBeAg-positive patients, but only serum HBcrAg was associated with cccDNA level (β = 0.774, P = 0.000) among HBeAg-negative patients. HBcrAg was better correlated with cccDNA as compared to HBsAg and HBV RNA, irrespective of HBeAg status. Among HBeAg-positive patients, though HBcrAg level was influenced by hepatic inflammatory activity and HBV DNA levels, the good correlations of HBcrAg with cccDNA persisted after stratification by inflammatory activity and HBV DNA levels. In conclusion, correlations of serum HBcrAg, HBV RNA and HBsAg levels differ significantly between HBeAg-positive and HBeAg-negative patients, but serum HbcrAg correlates with cccDNA levels better than HBV RNA and HBsAg, irrespective of HBeAg status.